The subject matter and content of audio and video productions varies greatly. In addition, to this variety there is, correspondingly, a considerable quantity of such audio and video productions. The quantity has been required to meet the demand from the broadcast and entertainment industries. The audio productions include, for example, radio broadcasts, both live and pre-recorded, musical and audio recordings, whereas video productions include, for example, films, television programs and video recordings. As will be appreciated typically video productions also include an accompanying sound track or commentary, so that an audio production is inherently included as part of the video production.
The term audio and/or video will be used herein to refer to any from of audio information or signals, video information or signals, or a combination of video and audio information or signals. The term audio/video will be used for short to refer to audio and/or video.
As a result of the great variety and considerable quantity of audio/video productions, the task of locating particular content items of audio/video material within an archive of audio/video productions represents an arduous and labour intensive task, because an operator must visually search the audio/video productions for the desired content item. Furthermore, because of the length of audio/video productions which are typically although not exclusively stored on linear recording media, the task of navigating through the media to locate particular content items of audio/video material from an audio/video production is time consuming and labour intensive.
The content of audio/video material is typically stored in a form which does not readily allow access to the content of the audio/video signals. This is particularly so, if the audio/video signal is compressed in some way. For example video cameras and camcorders are arranged conventionally to record a video signals representing the moving images falling within a field of view of the camera on a video tape. Once the video signals have been recorded on to the video tape, a user cannot determine the content of the video tape without reviewing the entire tape. Furthermore, because video tape is an example of a linear recording medium, the task of navigating through the media to locate particular content items of video material is time consuming and labour intensive. As a result during an editing process in which selected items from the contents of the video tape are combined in an order which may be different to that in which they were recorded, it may be necessary to review the entire contents of the video tape in order to identify the selected items. As will be understood from the foregoing discussion the audio/video material may be recorded on any medium, so that it remains a technical problem to identify the content of audio/video material for post production and achiving regardless of the recording medium, which may be a disc or a tape.